Apparatus for producing granulated slag



Jan. 17, 1950 J. A. HALKINS APPARATUS FOR PRODUCING GRANULATED SLAG 3 Sheets-Sheet 1 Filed Oct. 22, 1945 HUMMmJI Jan. 17, 1950 J. A. HALKINS 2,494,999

APPARATUS FOR PRODUCING GRANULATED SLAG Filed Oct. 22, 1945 3 Sheets-Sheet 2 Jan. 17, 1950 H ms 2,494,999

APPARATUS FOR PRODUCING GRANULATED SLAG Filed 0ct.'22, 1945 s Sheets-Sheet s 92 52 E i a2 o o a o Patented Jan. 17, 1950 UNITED STATES PATENT OFFICE APPARATUS FOR PBODUCING GRANULATED LAG James A. Hallrins, Bethlehem, Pa., assignor to The Waylite Company, a corporation of Illinois '4 Claims.

This invention 'relates to improvements in the apparatus for producing granulated or expanded slag which may be utilized in the manufacture of light weight aggregate.

In the past granulated or expanded slag has been produced by subjecting molten slag, such as from a blast furnace, to the addition of carefully regulated quantities of water and violently agitating and breaking up and dispersing the slag into relatively small expanded or granulated particles. The dispersed particles of slag were partially cooled during this process and when they fell on and were collected by a moving conveyor the particles tended to adhere and form semi-molten or sticky masses, sometimes referred to as tafly masses. These masses were then further cooled and later ground or crushed into the proper size aggregate. Such a method of' producing granulated or expanded slag for the production of light weight aggregate has been utilized by the Waylite Company for some time and is disclosed in Edgar E. Brosius Patent No. 2,023,511, granted December 10, 1935.

In that process, when the particles fell upon the conveyor, they tended to adhere to one-another in an uncontrolled manner, thus forming masses on the conveyor varying in size from a sand'particle to a boulder. As a result, an undesirable amount of fine size aggregate was produced, in part, by the small particles which fell on the moving conveyor and which failed to adhere and form into masses, and in part by breaking up of the masses because of uneven cooling. Also, the masses formed on the moving conveyor varied in size from time to time. The cell structure of the small masses was not as strong or uniform as in the large masses and an undesirable amount of surface material was present, the surface material being not as desirable as the material inside of the skin surface. Also the masses produced were somewhat spo y in character which produced uneven cooling resulting in fissures or shrinkage cracks.

The principal object of this invention is to improve the above mentioned process for producing granulated or expanded slag in order to reduce the percentage of fine size aggregate, to reduce the percentage of surface material, to provide a stronger and more uniform cellular structure, and to reduce the fissures or shrinkage cracks to a minimum. In carrying out this principal object of the invention, the following improvements, also forming objects of this invention, are utilized: an improved expansion or granulating arrangement; an improved agitating, die

recting and dispersing arrangement; and an improved arrangement for producing, in a controlled manner, large masses from the dispersed particles. While these improvements are separately important in producing the ultimate desired light weight aggregate, they also functionally cooperate to that end.

In regard to the first mentioned improvement, a vertically arranged expansion chamber is utilized for expanding the molten slag with water, carefully controlled in amount, pressure and manner of application, while it is freely falling through the expansion chamber. This prevents clogging of the chamber and provides more uniform expansion of the slag with a resultant more uniform cellular structure in the ultimate product.

The second improvement includes a novel beater wheel which in addition to agitating and dispersing, in an improved manner, the particles of expanded slag flowing from the expansion chamber, also directs the particles downwardly and inwardly, in an unimpeded manner, onto the collecting surface'where the semi-molten masses form whereby more uniform masses are obtained.

As to the third improvement, the semi-molten masses are subjected to a compression force, such as by mechanically compressing the same in a controlled manner, for gathering together the semi-molten masses and compressing them into larger masses. As a result, the percentage of fine particles and surface materials are appreciablyreduced and a stronger and more uniform cell structure is obtained. The larger masses are more compact causing slower cooling which results in better annealing and therefore less fissures or shrinkage cracks.

Further objects of this invention are to provideimproved apparatus for producing granulated slag.

Other objects and advantages of this invention will become apparent to those skilled in the art upon reference to the accompanying specification, claims and drawings in which:

Fig. 1 is an elevational view, partly in section, showing the preferred form of the apparatus of this invention;

Fig. 1A is a partial sectional view through one of the beaters;

Fig. 2 is a sectional view taken substantially on the line 2-2 of Fig. 1;

Fig, .3 is an elevational view, partly in section, taken substantially on the line 3-3 of Fig. 1;

Fig. .4 is a plan 'sectional'view showing-a modi e rm O t e a pa u Fig. is an elevational view, partly in section, of the modified form of the apparatus shown in Fig. 4;

Fig. 6 is an elevational and sectional view of a further modification of the apparatus;

Fig. '7 is a view similar to Fig. 6 showing the parts of the apparatus in different positions; and

Fig. 8 is a partial sectional view taken substantially on the line 88 of Fig. 6.

Referring now to the preferred form of the invention shown in Fig. 1, molten slag, such as slag from a blast furnace, is fed into the apparatus by a chute ID. The apparatus for subjecting the molten slag to the addition of water,

carefully regulated as to amount, force andmanner, and violently agitating, dispersing and directing the slag into relatively small, expanded particles for producing the semi-molten masses, is generally designated at l l. The portion of the apparatus for applying the compression force to the semi-molten masses is generally designated at l2, and this portion of the apparatus feeds on to a conveyer l3 wherein the masses of granulated or expanded slag are carried away for further cooling and crushing.

The portion of the apparatus generally designated at I I includes an annular wall l5 carried by suitable framework l6 to form a particle dispersion chamber H. A superstructure l8 carries a vertically arranged rotatable shaft I9 which is driven through bevel gearing 20 by a shaft 2| which in turn is driven in any suitable manner, as by a pulley 22. The lower end of the shaft l9 extends into the particle dispersion chamber I! and carries a plurality of beaters- 23. As shown, the assembly carrying the beaters 23 is water cooled. The beaters 23 are substantially triangular shaped as shown in Fig. *1A and act as a propeller for directing particles engaged thereby downwardly. Also the heaters 23 are not radially disposed but are inclined forwardly with the outer ends of the heaters leading the inner ends. This has the effect of directing the particles engaged thereby inwardly as well as downwardly. I

The molten slag supplied by the chute l0 empties into a vertical water cooled hopper 25 which forms a vertically disposed water cooled expansion chamber 26. The trough It is preferably so shaped that the molten slag is caused to fall freely through the vertical expansion chamber 26 in a relatively wide and thin stream or path. Spray nozzles 21 disposed on each side of the fiat stream of molten slagdirect, under high pressure, controlled amounts of water into the slag stream which expands the slag into small particles. The amount of water, the force of the water, and the locations of the nozzles 21 are so arranged and controlled as to penetrate the slag stream and cause the required amount of slag expansion with the least amount of water. The water also has a tendency to partially cool the slag and the partially cooled expanded slag falls freely from the expansion chamber 26 onto the heaters 23 which are rotated at a substantially constant speed. By expanding the slag in its freely falling condition, as pointed out above, uniform expansion to the desired degree is obtained with the least amount of water and without piling up of slag in the expansion chamber 26. This materially assists in obtaining a uniform cell structure in the ultimate material.

As the heaters 23 beat the expanded slag, it is further dispersed into small particles in the particle dispersion chamber and the majority of 4 the particles are directed downwardly and. inwardly through the directing or collecting chamber 34.

The water supplied to the water cooling assembly carrying the heaters 23 is carefully regulated through the pipe 28 and Water escapes from the assembly through the annular opening 29 to cause still further expansion and cooling of the slag. The annular wall I5 forming the particle dispersion chamber I! is preferably provided with internal Wearing plates 30 for the particles which are not directed inwardly and downwardly by the boaters 23.

The particles of slag are directed downwardly and inwardly through the directing or collecting chamber 34 formed by a water cooled hopper 33' onto a collecting surface formed by a water cooled trough 35 having upstanding water cooled sides 36. As the particles of expanded slag arrive at the water cooled trough 35 they arrive there with some force and they are, therefore forcefully piled up upon one another and tend to adhere to one another to form semi-molten masses of expanded slag. This action also materially assists in producing the desired cell structure in the ultimate product. Those particles of expanded slag which are not directed by the heaters 23 directly to the trough 35 are collected by the hopper 33 and delivered to the trough 35 in a semi-molten state which also tend to adhere to the particles or masses in the trough 35.

A water cooled reciprocating plunger 38 operates in the trough 35 underneath the hopper 33. This plunger 38 is provided with projections 39 carrying shafts 40 upon which are mounted wheels 4|. The wheels 4| roll in guides in the form of channels 42 carried by the framework I 6. The wheels 4|, therefore, support the plunger 38 for reciprocation back and forth beneath the hopper 33.

A pair of levers 44 are provided at one end with slots 45 for accommodating one of the shafts 40 and are pivoted at their other ends on a shaft 46 carried by suitable brackets 4'1. Extending between the pair of levers 44 is a shaft 48 to which is secured one end of a link 49. The other end of the link 49 is connected to a pin on a crank disc 50 which in turn is rotated through a reduction gear assembly 5| by means of a motor such as an electric motor 52. As the motor 52 rotates, the crank disc 50 causes the pair of arms 44 to be oscillated about their stationary pivot 46 to impart reciprocating motion to the water cooled plunger 38.

When the water cooled plunger 38 is retracted to the position shown in dot and dash lines, the

semi-molten particles directed from the collecting or directing chamber 34 on to the bottom of the trough 35. As the plunger 38 moves to the right to the solid line position, the semi-molten masses of slag are gathered and pushed along the trough 35. The trough provides a resistance to movement of the semi-molten slag, and because of this resistance to movement, the semimolten Slag is mechanically compressed as it is moved along the trough by the reciprocating motion of the plunger 38. This mechanical compression of the semi-molten masses as they move along the trough 35 causes large masses to be produced, causes the particles forming the masses to more firmly adhere and compresses the contents of the masses into a uniform condition thereby providing a compact and uniform cellular struccellular structure thus obtaining, the subsequent The amount of compression-force applied tothe masses of expanded 'slagas they move along the trough 35 depends-upon the length of the trough 35 and the. frequency of reciprocation ofthe-plunger 38'. The amount of compressionforceapplied, therefore, may be regulated byadjusting the speed of the motor 52 or by changing-the gearratio in the gearreductim mechanism or by changing the length of the trough 35. In this way the adhesive characteristic of the particles.

and the cellular structure of the expanded slag may be controlled to produce desired results. v Referring now to the modified form of apparatusshcwn in Figs. land 5, the portion of the apparatus generally designated at i i for expanding and dispersing the. molten slag into semi-- molten particles may be the same as shown in Fig. land like reference characters for like parts have been utilized. In Figs. 4 and 5 a hopper 59 provides a collectingv or directing chamber 60. The hopper 59 is provided with an opening til at its lower portion on one side where the semi-' molten masses may be extruded. Located immediately below the hopper 59 is a rotating disc 62 carried by a shaft 63 driven by a suitable gear reduction mechanism 54. The gear reduction mechanism 6d maybe driven'in any suitablemanner as by an electricmotor, not shown. Extending through an opening in the side wall of the hopper 59 is a stationary water cooled abutment 66 carried by the framework It. This stationary abutment 66 is located immediately above the rotating disc 62 outwardly to one side of the opening 6i in the hopper 59.

As the particles are directed from the collecting or directing chamber 68 onto the rotating disc 62, they are carried around by the rotating disc 62 into engagement with the stationary abutment 66, and because of the relative movements between the rotating disc 52 and the stationary abutment 65, the semi-molten masses of particles are compressed to provide greater adhesion between the particles and to improve the cellular structure of the slag. The semi-molten slag piling up against the stationary abutment 66 then moves laterally along the abutment tit out through the opening 6| in the hopper 59 onto a conveyor, not shown, for further cooling. Around the disc 62 is a stationary trough 61 for collecting slag which may escape between the hopper 59 and the disc 62. The disc 52 is provided with a paddle 68 operating in the trough 6! for scraping the leakage slag from the trough 61 and placing it on the conveyor, not shown.

In order to assist in the extrusion of the semimolten mass from the hopper 59 and disc 62, a water cooled plunger ill may be utilized. This plunger 19 is carried by an arr-1 H pivoted to the framework It at 12. The plunger is arcuate in shape with a radius coinciding with that of the shaft 12 and extends through an opening in the side wall of the hopper 59. The piston of an expansible chamber motor 14 carried by the frameworklBis pivotedto'th'e arm I l at 13 so that upon. operation of expansible chamber motor 14, the

plunger Ill is moved through an arcuate path into andout of the hopper59 and across the surfaced the disc 62. retractedpositiomand when it is advanced to the position showniin dot and dash lines, it assists in extruding the: semi-molten mass piling on the disc 62 in front of the stationary abutment 66. While the=detai1sofconstruction of the modification shown in Figs. 4 and 5 are different from those of the arrangement shown in Fig. 1, they are generally similar in function and operate to produce substantially-the same method and results.

In the further modification shown in Figs. 6, 7 and 8, the portion of the apparatus generally designated at I l in Fig. 1 is omitted.for simplicity of illustration. It is contemplated that that apparatus of Fig. 1' may be utilized with the con-.

In this IllOdir' struction shown in Figs. 6, 'Z and 8. fiedarrangement a hopper ll provides a collecting or directing chamber 18 for directing the particles of slag from the particle dispersion cham-. ber; The bottom of the hopper 7! is water cooled at 19. The hopper directs the particles into a chamber formed by stationary water cooled side walls -8I, a movable bottom wall 82, a movable end wall formed by a plunger-92 and a normally stationary end wall 86;

The movable bottom wall 82 is provided with rails 83 rolling. on rollers 84 suitably carried by the framework It. The movable bottom: wall 82' is: moved by a piston of an expansible chamber motor 85 also suitably carried by the frame- Work [6.

The normally stationary water cooled end: wall 86 is carried by part8! rolling on rollers 88 car-'- ried by a framework 89 suitably carried by the framework 16. A spring 9!! normally maintains the end wall 86 in the position shown in the drawings.

The water cooled plunger 92 forming the other movable end wall of the chamber 80 carries brackets 93 which are provided with rails 94 rolling on rollers 95 suitably carried through brackets 96 by the framework It. The plunger 92 is operated by the piston of an expansible chamber motor 91. This arrangement also utilizes a water cooled extruding plunger 99 operated by the piston of an expansible chamber motor I00.

With the parts in the position shown in Fig. 6, the particles of slag fall upon the bottom wall 82 to form a semi-molten mass. The plunger 92 is then advanced to the position shown in Fig. 7 for compressing and concentrating the mass into the relatively small chamber 81!. If the compression force caused by the right hand movement of the plunger 52 should be too great, the spring 9!] gives and the normally stationary wall 86 moves to the right. By adjusting the tension of the spring 90, the amount of compression applied to the mass in the chamber 88 may be varied. With the parts in the position shown in Fig. 7, the movable bottom wall 82 is then moved to the left and the extruding lunger 99 is moved downwardly to force the compressed semi-molten mass onto the conveyor is for further cooling. Following this, the movable bottom wall is again moved to the right, the plunger 99 is raised and the plunger 92 is moved to the left so that the parts again assume the position shown in Fig. 6. Here again, while the details of construction of the modification shown in Figs. 6, '7 and 8 differ from the details of construction of the other ar- The plunger is shown in the rangements, the general principles of operation are substantially the same, and the same method is performed and the same results are obtained.

While for purposes of illustration various forms of the apparatus have been disclosed for performing the methods of the invention, other forms thereof may become apparent to those skilled in the art upon reference to this disclosure, and, therefore, this invention is to be limited only by the scope of the appended claims and prior art.

I claim as my invention:

1. In an apparatus for producing from molten slag an expanded slag adaptable for use in producing light weight aggregate, the combination of means for expanding the molten slag into relatively small particles and for partially cooling the particles, and means for collecting the particles into a semi-molten mass and for applying a compression force to the semi-molten mass, said last mentioned means including a collecting surface for receiving the semi-molten mass and abutment means for moving the semi-molten mass relatively to the-collecting surface.

2. In an apparatus for producing from molten slag an expanded slag adaptable for use in producing light weight aggregate, the combination of means for expanding the molten slag into relatively small particles and for partially cooling the particles, and means for collecting the particles into a semi-molten mass and for applying a compression force to the semi-molten mass, said last mentioned means including a trough for collecting the semi-molten mass and an intermittently operated plunger for advancing the mass along the trough.

3. In an apparatus for producing from molten slag an expanded slag adaptable for use in producing light weight aggregate, the combination of means for expanding the molten slag into relatively small particles and for partially cooling the particles, and means for collecting the particles into a semi-molten mass and for applying a compression force to the semi-molten mass, said last mentioned means including a receptacle for collecting the semi-molten mass, a plunger for compressing the mass in the receptacle and means for extruding the compressed mass from the receptacle.

4. In an apparatus for producing from molten slag an expanded slag adaptable for use in producing light weight aggregate, the combination of a vertically disposed expansion chamber to receive freely falling molten slag, spray nozzles in the expansion chamber for subjecting the freely falling molten slag to water sprays carefully regulated as to force and quantities of water, a collecting surface below the expansion chamber, heaters disposed between the expansion chamber and the collecting surface for violently agitating and dispersing the slag falling from the expansion chamber and for forcefully directing it onto the collecting surface, and means for applying a compression force to the slag on the collecting surface.

JAMES A. HALKINS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

